1. Field of the Disclosure
The present disclosure relates to a touch screen panel and a display device.
2. Description of the Prior Art
Recently there has been much focus on display devices such as a liquid crystal display device, a field emission display device, a plasma display device, etc. due to their rapid response speed, low power consumption, and an excellent color reproduction rate. Such display devices are used for various electronic devices such as a TeleVision (TV), a computer monitor, a notebook computer, a mobile phone, a display unit of a refrigerator, a Personal Digital Assistant (PDA), an Automated Teller Machine (ATM), etc. In general, such display devices configure an interface with a user using various input devices such as a keyboard, a mouse, a digitizer, etc.
However, there is a problem in that, in order to use a separate input device such as a keyboard, a mouse, etc., a user should become proficient in a method of using them and the separate input device occupies a space, thereby causing user's dissatisfaction. Thus, an input device, which is convenient and simple and can reduce malfunctions thereof, has been demanded more and more. According to the demand, a touch screen panel, to which a user inputs information by making a finger or a pen thereof directly contact a screen, has been proposed.
The touch screen panel is classified into a resistive scheme which determines a touched portion by using a voltage gradient according to a resistor in a state in which a metal electrode is formed on an upper plate or a lower plate thereof to apply a direct current voltage thereto, a capacitive scheme which detects a touched portion by detecting a location where a change in voltage of the upper/lower plate according to a touch in a state in which an equipotentiality is formed on a conductive film, and an electromagnetic scheme which detects a touched portion by reading an LC value induced due to a touch on a conductive film by an electronic pen, according to a scheme of detecting a touched portion. In addition, an optical scheme and a surface acoustic wave scheme have been known.
The capacitive scheme has a matrix formed by intersecting electrode patterns, and has an advantage in that, when a touch is generated at a predetermined location on the matrix, a touched location is detected by finding an X-axis coordinate and a Y-axis coordinate on the matrix where a capacitance thereof is varied, thereby detecting the touched location even when a contact force is small.
However, a capacitive type touch screen panel according to the related art has a problem in that, since a shape or a width of electrodes formed at a lower portion of a cover may not be uniform, when the thickness of the cover is not uniform due to importance of design of a product, accuracy in detecting a change in a capacitance is reduced.